The impact of parent-child relationship on adolescent social adjustment following childhood abuse: the moderation of the serotonergic multilocus genetic variation.

Introduction: Childhood adverse experiences appear to increase sensitivity to stress, potentially influencing lifelong social adjustment. Previous studies suggest that serotonergic multilocus genetic variation moderates the relationship between environmental factors and social adjustment. Methods: This study investigated an adolescent sample (mean age 14.15 ± 0.63 years; N = 700), using theory-driven multilocus genetic profile scores (MGPS) to measure serotonergic multilocus genetic variation. Leveraging longitudinal data, we examined the interactions between serotonergic MGPS, childhood abuse (CA), and parent-child relationship and their impact on three adolescent adjustment outcomes: depressive symptoms, aggressive behavior, and creativity. Results: The findings revealed significant gene × environment × environment (G × E × E) interactions among serotonergic MGPS, CA, and parent-child relationship that predicted depressive symptoms in the mother-child model and aggressive behavior in both father-child and mother-child models. In contrast, creativity was predicted by a significant gene × environment (G × E) interaction between serotonergic MGPS and parent-child relationship, whereas no significant G × E × E interaction was found. Conclusions: This study highlights that adolescent social adjustment may reflect the interplay of genetic factors (serotonergic MGPS), distal experiences (CA), and proximal environmental influences (parent-child relationship), providing new insights into the mechanisms underlying adolescent social adjustment through the lens of gene-environment interactions.